Optical apparatus

ABSTRACT

An optical apparatus including a substrate, a light-emitting module, a transparent optical element and a connecting unit is provided. The light-emitting module is disposed over the substrate and is electrically connected with the substrate. The transparent optical element is disposed over the light-emitting module. The transparent optical element includes a transparent substrate and an optical element. The optical element is disposed on the transparent substrate. The optical element and the transparent substrate are integrally formed and made of a same material. The connecting unit is disposed beside the light-emitting module and is used for connecting the transparent optical element to the substrate.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application serial no. 107124245, filed on Jul. 13, 2018. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND Technical Field

The disclosure relates to an apparatus, and more particularly to an optical apparatus.

Description of Related Art

The method of imprinting is often adopted for a conventional optical element to imprint a specific pattern on a transparent substrate as optical structures. Such method often uses an organic material such as epoxy, etc. as the material of the patterned optical structures.

However, when the optical element is collided, the optical structures made of organic material are more prone to abrasion or scratching. In addition, when the above optical element is applied to a high-intensity light-emitting element, under a long period of use, the optical structures made of organic material may photo- or thermal-degradation due to continuous exposure to light source irradiation, thereby affecting the optical property or optical behavior of the optical element.

SUMMARY

Embodiments of the disclosure provide an optical apparatus having stable optical properties.

An embodiment of the disclosure provides an optical apparatus including a substrate, a light-emitting module, a transparent optical element, and a connecting unit. The light-emitting module is disposed over the substrate and is electrically connected with the substrate. The transparent optical element is disposed over the light-emitting module. The transparent optical element includes a transparent substrate and an optical element. The optical element is disposed on the transparent substrate. The optical element and the transparent substrate are integrally formed and made of the same material. A material of the transparent optical element includes a crystal material. The connecting unit is disposed beside the light-emitting module and is used for connecting the transparent optical element to the substrate.

In an embodiment of the disclosure, the crystal material includes sapphire or spinel.

In an embodiment of the disclosure, the optical element is disposed on at least one of a first surface of the transparent substrate and a second surface of the transparent substrate opposite to the first surface.

In an embodiment of the disclosure, the transparent optical element includes a diffractive optical element or a lens array.

In an embodiment of the disclosure, the connecting unit surrounds the light-emitting module and maintains a distance between the light-emitting module and the transparent optical element.

In an embodiment of the disclosure, the orthographic projection area of the transparent optical element on the substrate is less than the area of the substrate.

In an embodiment of the disclosure, the light-emitting module includes a laser diode or a light-emitting diode.

In an embodiment of the disclosure, the connecting unit is an annular glue frame.

Based on the above, in the optical apparatus of the embodiments of the disclosure, since the optical element and the transparent substrate of the transparent optical element are integrally formed and made of the same material, the optical element of the embodiments of the disclosure is less prone to photo- or thermal-degradation as compared to the optical element made of organic material, thus the optical element of the embodiments of the disclosure can have stable optical properties.

To make the aforementioned and other features of the disclosure more comprehensible, several embodiments accompanied with drawings are described in detail as follows.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1 is a cross-sectional schematic view of an optical apparatus according to an embodiment of the disclosure.

FIGS. 2A to 2C are schematic views of a manufacturing process of a transparent optical element according to an embodiment of the disclosure.

FIG. 3 is a block diagram of a manufacturing process of an optical apparatus according to an embodiment of the disclosure.

DETAILED DESCRIPTION OF DISCLOSED EMBODIMENTS

FIG. 1 is a cross-sectional schematic view of an optical apparatus according to an embodiment of the disclosure. Referring to FIG. 1, an optical apparatus 100 of the embodiment includes a substrate 110, a light-emitting module 120, a transparent optical element 130, and a connecting unit 140. The light-emitting module 120 is disposed over the substrate 110 and is electrically connected with the substrate 110. The transparent optical element 130 is disposed over the light-emitting module 120. The transparent optical element 130 includes a transparent substrate 132 and an optical element 134. The optical element 134 is disposed over the transparent substrate 132. The optical element 134 and the transparent substrate 132 are integrally formed and made of the same material. The connecting unit 140 is disposed beside the light-emitting module 120 and is used for connecting the transparent optical element 130 to the substrate 110.

Since the optical element 134 and the transparent substrate 132 of the transparent optical element 130 are integrally formed and made of the same material, the optical element 134 of the embodiment of the disclosure is less prone to photo- or thermal-degradation as compared to an optical element made of organic material, thus the optical element 134 of the embodiment of the disclosure can have stable optical properties.

In the embodiment, the light-emitting module 120 is, for example, a vertical-cavity surface-emitting laser (VCSEL) module which can emit multiple light beams. In other embodiments, the light-emitting module 120 may be an edge-emitting laser diode module which emits a single light beam, a light-emitting diode (LED) module, or other suitable light sources. Also, the number of light source may be one or multiple, and the disclosure is not limited thereto.

In the embodiment, the optical element 134 is disposed on at least one of a first surface S1 of the transparent substrate 132 and a second surface S2 of the transparent substrate 132 opposite to the first surface S1. Specifically, as shown in FIG. 1, the optical element 134 is disposed on the first surface S1, of the transparent substrate 132, away from the light-emitting module 120. However, in other embodiments, the optical element 134 may be disposed on the second surface S2, of the transparent substrate 132, close to the light-emitting element 120. Alternatively, the first surface S1 and the second surface S2 of the transparent substrate 132 may be disposed with the optical element 134 at the same time.

It shall be noted that the transparent optical element 130 shown in FIG. 1 is exemplified using a lens array, that is, the optical element 134 is exemplified using multiple microlens structures. However, the transparent optical element 130 may be a diffraction optical element (DOE) alternatively while the optical element 134 is multiple diffraction microstructures. When the transparent optical element 130 is a DOE or a lens array, the optical apparatus 100 is adapted to be applied to a light detection technology. Alternatively, in other embodiments, the optical element 134 may be a single-lens structure, Fresnel lens microstructures, or other optical structures, and the disclosure is not limited thereto.

In the embodiment, the material of the transparent optical element 130 includes a crystal material, such as sapphire. In other words, both of the optical element 134 and the transparent substrate 132 are made of a crystal material, such as sapphire. Specifically, sapphire has characteristics such as high hardness, high melting point, high refractive index, etc. Sapphire has a Mohs' hardness of 9 and is a material of high hardness and abrasion-resistance, thereby allowing the optical element 134 of the transparent optical element 130 to be less prone to damage. Furthermore, sapphire has a melting point of more than 2000 degrees Celsius and good thermal conductivity, so deformation is less likely to occur even under a long period of exposure to light source irradiation, which contributes to maintaining stable optical properties of the transparent optical element 130. In addition, sapphire has a refractive index of approximately 1.74 and is a material of high refractive index, thereby achieving better light beam expansion effect, which is advantageous for the application of the transparent optical element 130. For example, when the optical apparatus 100 is applied to light detection technology, even if the object to be detected is at a close distance, the entire area of the object to be detected may be covered due to the better light beam expansion effect. On the other hand, since the light beam expansion effect is better, an optical element with a smaller size can be used to achieve the same light-expansion effect, which is advantageous for the size-minimizing of the optical element.

It is worth mentioning that since atoms or molecules inside a crystal material are regularly arranged, the shape of the optical element 134 can be presented similar to the shape of a microlens structure by directly using an anisotropic etching method without a complex process.

In other embodiments, the material of the transparent optical element 130 may be other crystal materials with high transparency, abrasion-resistance, or are less likely to be affected by temperature of light source. For example, the material of the transparent optical element 130 may be spinel. Spinel has a Mohs' hardness of 8, a refractive index of more than 1.7, and a high melting point, so spinel has advantages similar to those of sapphire. However, in some embodiments, the material of the transparent optical element 130 may be glass or other suitable transparent materials, and the disclosure is not limited thereto.

It shall be noted that the embodiment is exemplified using a single-layer transparent optical element. However, in other embodiments, the transparent optical element may be a composite structure formed with multiple layers of stacked optical elements.

In the embodiment, the connecting unit 140 surrounds the light-emitting module 120, and maintains a distance between the light-emitting module 120 and the transparent optical element 130. The connecting unit 140 is, for example, an annular glue frame. The connecting unit 140 surrounds and encloses the light-emitting module 120, and allows the transparent optical element 130 to join to the substrate 110 disposed with the light-emitting module 120. In addition, the orthographic projection area of the transparent optical element 130 on the substrate 110 is less than the area of the substrate 110. In other words, a portion of the substrate 110 is exposed outside the transparent optical element 130, allowing an external connection (for example, an electrode connection) of the light-emitting module 120 to be externally connected through the exposed portion of the substrate.

FIGS. 2A to 2C are schematic views of a manufacturing process of a transparent optical element according to an embodiment of the disclosure. Referring to FIG. 2A to FIG. 2C, firstly, as shown in FIG. 2A, a transparent substrate material 132′ is provided. Next, as shown in FIG. 2B, a patterned mask PM is formed on the transparent substrate material 132′. In the embodiment, the patterned mask PM may be imprinted onto the transparent substrate material 132′ through an imprinting process. Alternatively, the patterned mask PM may be a patterned photoresist formed through a photolithography process. Finally, as shown in FIG. 2C, an etching process is performed on the transparent substrate material 132′ formed with the patterned mask PM so as to form an optical element 134 a, and then the patterned mask PM is removed. Therefore, the completed transparent substrate 132 a and the optical element 134 a of the transparent optical element 130 a are integrally formed and made of the same material. In the embodiment, the etching process may be dry etching or wet etching. Since the optical element 134 a is formed by the etching process, advantages such as stability and/or uniformity may be achieved. Furthermore, the contour of the optical element 134 a may be easily optimized to achieve desired optical requirement.

It shall be noted that the appearance and manufacturing method of the transparent optical element 130 a are merely illustrative examples, and are not intended to limit the disclosure. Any optical element 130 a with the transparent substrate 132 a and the optical element 134 a integrally formed and made of the same material, and the method of manufacturing the same are included in the protected scope of the disclosure.

FIG. 3 is a block diagram of a manufacturing process of an optical apparatus according to an embodiment of the disclosure. A method 200 of the embodiment may adopt a wafer level manufacturing method to join transparent optical elements to a substrate disposed with light-emitting modules. This manufacturing method does not require a chip level manufacturing method which uses a more complex alignment process to join an independent optical element to an individual substrate disposed with a light-emitting module one by one. Therefore, this manufacturing method of the embodiment is simpler and has a lower cost.

Referring to FIG. 3, the method 200 of the embodiment is, for example, for manufacturing the optical apparatus 100 of FIG. 1. Before performing a singulation cutting process, multiple optical apparatuses 100 are connected to each other and are arranged, for example, in an array. In Step 202, a substrate is provided. In Step 204, light-emitting modules are disposed over the substance. In Step 206, a transparent substrate material, such as the transparent substrate material 132′ in FIG. 2A, is provided. In Step 208, transparent optical elements are formed using, for example, the method illustrated in FIG. 2A to FIG. 2C. In Step 210, the transparent optical elements are joined to the substrate disposed with the light-emitting modules through the connecting units. In Step 212, singulation cutting is performed to individualize multiple independent optical apparatuses 100.

In the embodiment, two cutting processes may be performed to make the area of the transparent optical element of the optical apparatus after cutting smaller than the area of the substrate of the optical apparatus. The first process is to cut the transparent optical element from the side close to the transparent optical element (such as the upper part of FIG. 1) and the second process is to cut the substrate from the side close to the substrate (such as the lower part of FIG. 1). Alternatively, cutting may be performed from the same side and cutting energies (for example, energy of laser) at different depths are controlled to make the area of the transparent optical element of the optical apparatus after cutting smaller than the area of the substrate of the optical apparatus, so as to facilitate an external connection of the light-emitting module.

It is worth mentioning that the optical element of the transparent optical element of the embodiment may be formed on the transparent substrate material in a uniformly distributed form, so that there is no need to align the optical element of the transparent optical element with the corresponding light-emitting module one by one through an additional alignment process. Therefore, the manufacturing method is simpler. However, in other embodiments, the optical element may correspond to only the position directly above the light-emitting module, and the disclosure is not limited thereto.

In summary, in the optical apparatus of the embodiments of the disclosure, since the optical element and the transparent substrate of the transparent optical element are integrally formed and made of the same material, the optical element of the embodiments of the disclosure is less prone to photo- or thermal-degradation as compared to the optical element made of organic material, thus the optical element of the embodiments of the disclosure can have stable optical properties. Furthermore, when a material such as sapphire or spinel is adopted as the material of the transparent optical element, since this kind of crystal materials have characteristics such as high refractive index, high hardness, high temperature-resistance, etc., the transparent optical element made of this kind of crystal materials can have advantages such as better light beam expansion effect, higher abrasion-resistance, less prone to deformation, etc.

Although the disclosure has been disclosed by the embodiments above, the disclosure is not limited to the embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made to the disclosed embodiments without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the disclosure covers modifications and variations provided that they fall within the scope of the following claims and their equivalents. 

What is claimed is:
 1. An optical apparatus, comprising: a substrate; a light-emitting module disposed over the substrate and electrically connected with the substrate; a transparent optical element disposed over the light-emitting module, wherein the transparent optical element comprises: a transparent substrate; and an optical element disposed on the transparent substrate, wherein the optical element and the transparent substrate are integrally formed and made of a same material, and a material of the transparent optical element comprises a crystal material; and a connecting unit disposed beside the light-emitting module and used for connecting the transparent optical element to the substrate.
 2. The optical apparatus according to claim 1, wherein the crystal material comprises sapphire or spinel.
 3. The optical apparatus according to claim 1, wherein the optical element is disposed on at least one of a first surface of the transparent substrate and a second surface of the transparent substrate opposite to the first surface.
 4. The optical apparatus according to claim 1, wherein the transparent optical element comprises a diffractive optical element or a lens array.
 5. The optical apparatus according to claim 1, wherein the connecting unit surrounds the light-emitting module and maintains a distance between the light-emitting module and the transparent optical element.
 6. The optical apparatus according to claim 1, wherein an orthographic projection area of the transparent optical element on the substrate is less than an area of the substrate.
 7. The optical apparatus according to claim 1, wherein the light-emitting module comprises a laser diode or a light-emitting diode.
 8. The optical apparatus according to claim 1, wherein the connecting unit is an annular glue frame. 